The problem for people comes when they know -- they just KNOW -- that multiboxing is illegal ...but when it comes to it, they can't think why this is. Why not just take a stab at it, even if they need to make up a little evidence, just to satisfy the conversation until they can remember the actual reason? They're confident of eventual vindication as a righteous person, being that they're 100% sure they're correct even if they can't quite put a finger on why that is, just at the moment.

I don't think this is usually a conscious train of thought, but I imagine it goes something like that. We've probably all been there once or twice, with something we'd just love to believe is true.